Rheumatology Flashcards
management of raynaud’s
- 1st line
- 2nd line
1st line: calcium channel blocker eg nifedipine
2nd line: IV prostacyclin (epoprostenol) infusion
what suggests primary raynaud’s (2)
<40y old
bilateral symptoms
what suggests secondary raynauds (6)
- unilateral onset
- rash
- older - >40
- autoantibodies
- fts suggestive of a CTD - arthritis, recurrent miscarriages, calcinosis
- digital ulcers; chillblains
secondary causes of raynauds (8)
- CTDs: scleroderma (most common), RA, SLE
- Leukaemia
- Type 1 cryogloublinaemia, cold agglutinins
- Use of vibrating tools
- Drugs: COCP, ergot
- Cervical rib (extra rib above 1st rib > thoracic outlet syndrome > raynauds)
patterns of psoriatric arthropathy
- symmetric polyarthritis (most common: 30-40% - like RA)
- asymm oligoarthritis - usually hands and feet. 20-30%
- sacroilitis
- DIP joint disease
- arthritis mutilans
Xray of psoriatric arthropathy
often have the unusual combination of coexistence of erosive changes and new bone formation
periostitis
‘pencil-in-cup’ appearance
other signs of psoriatric arthritis
psoriatic skin lesions
periarticular disease - tenosynovitis and soft tissue inflammation resulting in:
- enthesitis: inflammation at the site of tendon and ligament insertion e.g. Achilles tendonitis, plantar fascitis
- tenosynovitis: typically of the flexor tendons of the hands
- dactylitis: diffuse swelling of a finger or toe
nail changes: pitting, onycholysis
whats the first Ix to do for septic arthritis
synovial fluid sampling
- only dont do 1st if septic/unstable
abx for septic arthritis
IV fluclox - or clindamycin if pen allergic - for 6-12wks
common bacteria that cause septic arthritis
- staph aureus (most common)
- n gonorrhoea (young and sexually active)
most common site = knee
reactive arthritis symptoms
Triad of symptoms (cant see, pee or climb a tree)
Urethritis
Conjuncitivitis
Arthritis
reactive arthritis causes (bacteria)
STI (more common in men): chlamydia trachomatis
Dysentery: shigella flexneri, salmonella typhimurium, salmonella enteritidis, yersinina enterocolitica, campylobacter
reactive arthritis mx
Symptomatic: anlagesia, NSAIDs, steroid injections into the joint
Persistent disease: can use sulfasalazine, methotrexate
important
mx of ank spond
1st line: exercise + NSAIDs; physio
if persistently high disease activity despite this: anti-TNF therapy
DMARDS for RA only useful if peripheral joints involved (EG sulfasalazine)
XR changes seen in ank spond
Plain XR: most useful Ix in diagonsis - Can be normal early on LATER - Sacroilitis (subchrondral erosions, sclerosis) - Squaring of lumbar vertebrae - Bamboo spine - Syndesmophytes (ossification of outer fibres of annulus fibrosus [exterior of intervertebral disc]) - Apical fibrosis on CXR
If negative XR but high clinical suspicion > MRI
- Signs of early inflam involving SI joints (bone marrow oedema) confirm dx
paget’s disease: blood levels of calcium/phosphate/other tests
- normal value of calcium, phosphate
- high ALP
Other markers of bone turnover will be high:
- procollagen type I N-terminal propeptide (PINP)
- serum C-telopeptide (CTx)
- urinary N-telopeptide (NTx)
- urinary + serum hydroxyproline
paget’s disease: tx and indications for it
Indications for tx
- Bone pain
- Skull or long bone deformity
- Fracture
- Periarticular paget’s
Tx
- Bisphosphonate (oral risedronate or IV zoledronate)
- Calcitonin – less commonly used now
how to tell drug induced lupus and SLE apart
drug induced: dont tend to see renal or nervous system involvement.
negative Anti-ds-DNA antibodies. positive anti-histone antibodies
normal SLE: positive for dsDNA. negative for anti histone
dermatomyositis:
- Abs most specific
- Abs most common to it
most specific: Anti-Mi-2
most common: ANA
dermatomyositis fts
Proximal pain and tenderness Heliotrope sign (violaceous rash over eyelids) Shawl sign (rash over upper arms, shoulders & upper back)
dermatomyostitis tx
prednisolone
pseudogout: whats seen in the joint fluid
weakly positively birefringent rhomboid-shaped crystals
pseudogout RF
Haemochromatosis
Hyperparathyroid
Low Mg or low phosphate
Acromegaly, wilsons
pseudogout mx
Aspiration of joint fluid (to excl septic arthritis)
NSAIDs or steroids (into the joint, IM or oral)
prophyria cutanea tarda - mx
Chloroquine
Venesection if iron ferritin >600ng/ml
prophyria cutanea tarda - causes
Inherited defect in uroprophyrinogen decarboxylase
Hepatocyte damage – alcohol, hep C, oestrogen
porphyria cutanea tarda presentation
Photosensitive rash w blistering and skin fragility on face + dorsal aspect of hands
Oncholysis
Hypertrichosis (excessive hair)
Hyperpigmentation
impetigo - tx
1st line: hydrogen peroxide 1% cream (for systemically well and low risk of complications)
Next options
- Topical fusidic acid
- If resistant to this: topical mupirocin (could be MRSA)
Extensive disease:
- Oral fluclox
- Pen-allergic: oral erythromycin
bacteria that cause impetigo
Causes: staph aureus, strep pyogenes
uncontrolled psoriasis and psoriatric arthritis - tried NSAIDs and steroids - what now?
etanercept
what dose of steroids makes you want to offer osteoporosis prophylaxis
equiv of pred 7.5mg OD for 3 months
key XR change in ank spond
syndesmophytes: due to ossification of outer fibers of annulus fibrosus
Radiographs may be normal early in disease, later changes include:
sacroiliitis: subchondral erosions, sclerosis
squaring of lumbar vertebrae
‘bamboo spine’ (late & uncommon)
chest x-ray: apical fibrosis
COMPRESSION OF nerve root of
- L3
- L4
- L5
- S1
- L3: sensory loss over anterior thigh
- L4: sensory loss over anterior knee
both L3 & L4: weak quadriceps, reduced knee reflex, positive femoral stretch test - L5: sensory loss of dorsum/top of foot, weak foot and big toe dorsiflexion, positive sciatic nerve stretch test (reflexes intact)
- S1: sensory loss to posterolateral leg and lateral foot, weak plantar flexion, reduced ankle reflex, positive SN stretch test
osteogenesis imperfecta
whats the problem
type 1 collagen
Abs for dermatomyositis: most sens and most spec
Abs for polymyositis
dermato: ana most common, anti-mi-2 most specific
poly: anti-Jo-1
denosumab action?
RANK ligand inhibitor > inhibits maturation of osteoclasts
SLE
- most sensitive antibody?
- most specific?
- what Ab do they use for monitoring
- what happens to complement?
· Most sensitive = ANA: 99% +ve (high sensitivity = useful rule out test, but low specificity)
· Most specific = anti-smith
○ Anti-dsDNA and anti-Smith very specific >99% but less sensitive
○ Anti-dsDNA can be used for monitoring (but not present in all pts)
C3 and C4 levels low during active disease (formation of immune complexes > consumption of complement)
mx of RA
- 1st line
- 2nd line
- 3rd line
- whats rituximab?
- mx of flares?
1st line: DMARD and short course of prednisolone
- DMARD options: methotrexate, sulfasalazine, leflunomide, hydroxychloroquine
then try another DMARD
if not good response to 2: TNF inhibitor (Etanercept, infliximab, adalimumab)
Flares: mx w steroids (oral or IM)
EXTRA: rituximab (anti-CD20)
1st line mx of RA
DMARD and short course of prednisolone
antiphospholipid syndrome
- aptt?
causes a paradoxical rise in the APTT. This is due to an ex-vivo reaction of the lupus anticoagulant autoantibodies with phospholipids involved in the coagulation cascade
azathioprine
- can you use it in preg?
- what common drug does it interact with?
- SE (4)
- how does it work pharmaceutically
Key bits
· Safe in pregnancy
· Can interact w allopurinol - so use lower doses of azathioprine
Notes
· SE: BM depression, N&V, pancreatitis, increased risk of non-melanoma skin cancer
· Metabolised to mercaptopurine (active: a purine analogue that inhibits purine synthesis)
May need to do TPMT (thiopurine methyltransferase test) to look for pts prone toxicity
sulfasalazine
- if patients are allergic to X or Y they could react to sulfasalazine
- caution with what genetic condition?
- pharm action
- SE
- preg?
aspirin, sulphonamides
- Caution w G6PD deficiency
Notes
- Prodrug for 5-ASA - SE: oligospermia, SJS, pneumonitis/fibrosis, myelosuppression, Heinz-body anaemia, megaloblastic anaemia, stained contacts (can colour tears)
Details
- 5-ASA: decreases neutrophil chemotaxis + suppresses prolif of lymphocytes and pro-inflam cytokines
safe in preg and BF
drug induced lupus causes
- most common 2
- less common (3)
is the damage permanent
Most common
- procainamide (used for cardiac arrhythmias)
- hydralazine (diuretic: high BP)
Less common
- isoniazid (TB)
- minocycline (abx)
- phenytoin (epilepsy)
- Don’t get renal or nervous involvement usually
Resolves on stopping drug
- Don’t get renal or nervous involvement usually
heberden’s & bouchard’s nodes
what disease are they seen in, where are they, what are they and whats the cause
OA
Heberden’s nodes at the DIPJs, Bouchard’s Nodes at the PIPJs.
Painless nodes (bony swellings):
Due to osteophyte formation
RF for osteoporosis
Sig RF: female, older age
RF used by major risk assessment tools such as FRAX: • history of glucocorticoid use • RA • alcohol excess • history of parental hip fracture • low BMI • current smoking
Other RF
• sedentary lifestyle
• premature menopause
• Caucasians and Asians
• endocrine disorders: hyperthyroidism, hypogonadism (e.g. Turner’s, testosterone deficiency), GH deficiency, hyperparathyroidism, DM
• multiple myeloma, lymphoma
• GI: IBD, malabsorption (e.g. Coeliac’s), gastrectomy, liver disease
• CKD
• osteogenesis imperfecta, homocystinuria
Medications that may worsen osteoporosis (other than glucocorticoids):
• SSRIs • antiepileptics • PPIs • glitazones • long term heparin therapy aromatase inhibitors e.g. anastrozole
osteoporosis
- t score: what is it, values for normal/osteopenia/osteoporosis
- z score
Basics
T score: based on bone mass of young reference population
T score of -1.0 means bone mass of one standard deviation below that of young reference population
Z score is adjusted for age, gender and ethnic factors
T score
> -1.0 = normal
-1.0 to -2.5 = osteopaenia
< -2.5 = osteoporosis
ank spond comps
• Apical fibrosis • Anterior uveitis • Aortic regurgitation • Achilles tendonitis • AV node block • Amyloidosis • and cauda equina syndrome peripheral arthritis (25%, more common if female)